June to October is the dry season across northern Tanzania and the Serengeti–Mara, and the strongest all-round window. January to March is calving season on the southern Serengeti plains, with February the peak. March to May brings the long rains — quieter, cheaper, wetter.
For most trips, June to October. The Tanzania Meteorological Authority names June, July, August and September as the dry months across bimodal northern Tanzania, and the Serengeti–Mara ecosystem's dry season runs June to October. Grass is short, water is concentrated, roads hold up. If you want the wildebeest calving instead, come January to March, with February the peak.
For a first Tanzania safari that is usually right. But "best" depends on which Tanzania you mean: the country runs on two rainfall calendars, the migration follows rain rather than a schedule, and the month changes what you pay at the gate.
The Tanzania Meteorological Authority (TMA) divides the country into two rainfall regimes, and the northern and southern circuits are not on the same calendar.
TMA also names the dry windows for bimodal Tanzania: June, July, August and September are the dry months, and January and February are a relatively dry transition period. Those two windows are the backbone of northern-circuit planning, and everything below sits on top of them. TMA revises its climate statements on its own schedule, and any single year can run early or late.
| Window | What the weather does | What it is good for | The trade-off |
|---|---|---|---|
| June–September | TMA's named dry months in the bimodal north | Northern circuit game viewing; the Western Corridor in June and July, then north, with Mara River country from August; Zanzibar | TANAPA's lodge concession fee is at its peak rate from July to September |
| October–December | Vuli short rains in bimodal areas | The southward return, mostly October into early November; green landscapes | Afternoon storms; the collar-derived transition window is wide and shifts with rainfall |
| January–February | TMA: a relatively dry transition period | Calving on the southern short-grass plains — close to half a million calves in roughly three weeks | Confirm accommodation for your exact dates early; no authority publishes occupancy |
| March–May | Masika long rains | Serengeti's low-season conservation fee applies 15 March–15 May | The wettest months, and the ones where road conditions are worst |
Longer than most people expect, and less predictably than most websites suggest. The Convention on the Conservation of Migratory Species (CMS) is blunt about the mechanism: roughly 1.3 million migratory wildebeest, and "seasonal rainfall drives the wildebeest migration".
The closest thing to a defensible schedule comes from CMS, drawn from GPS collars on 62 animals tracked between 1999 and 2022. It gives windows, not dates:
CMS describes the year in sequence: females calve on the southern short-grass plains at the peak of the rains; with the onset of the dry season in May the herds move west; they retreat into the Western Corridor in June and July for sodium-rich grasses; then they push further north once the seasonal rivers run dry. The Mara River is their primary water source from August to October and the only permanently flowing river in the ecosystem — the real basis for the "crossing season" everyone talks about.
Two things temper all of it. Individual routes vary by a factor of five, from about 44 km to about 225 km, so the herds are a broad front rather than a dot on a map. And peer-reviewed work shows timing shifts with rainfall extremes in both directions: an unusually wet wet season delays the northward move, while drought brings it forward.
On river crossings, be sceptical of any month-by-month promise. No park authority, government agency or research body publishes crossing dates, and crossings are not tracked as discrete events at all. Anyone selling you a Grumeti or Mara crossing week is giving you operator expectation, which has value but is not a schedule. We will tell you where the herds usually are and where they might be, and we will not present that as more than it is. Our month-by-month migration guide sets out the pattern in full, and the Great Migration page covers how we build trips around it.
Yes. It is the one part of the migration year with a genuinely tight window. A 2018 study in Scientific Reports records nearly 500,000 calves born within roughly a three-week period, with measured synchrony running between about 20 and 29 days across years and herds. That traces back to an equally tight rut — Estes recorded 80% of females mating within a two-to-three-week window at its peak.
In practice, roughly 80–90% of calves arrive in a narrow three-week window falling somewhere between January and March, with February the peak month, and as many as 8,000 calves in a single day at the height of it. It happens on the short-grass plains of the Ndutu region in the southern Serengeti and the adjoining Ngorongoro Conservation Area. No authority publishes a calving month — CMS says only that calving occurs at the peak of the rainy season — so treat February as the strong centre of a wider window rather than a fixed date.
Yes, twice over, on two different calendars — a common source of quoting errors.
| Fee | Authority | Amount (foreign non-resident adult) | Season |
|---|---|---|---|
| Serengeti conservation fee | TANAPA | USD 70 per person per day peak; USD 60 low season. The tariff book states charges exclude 18% VAT, which makes them USD 82.60 and USD 70.80 with VAT | Peak 16 May–14 March; low 15 March–15 May |
| Serengeti lodge concession fee | TANAPA | USD 60 per person per night peak; USD 50 low. Also VAT-exclusive in the tariff book: USD 70.80 and USD 59.00 with VAT | Peak July–September only; low October–June |
| Ngorongoro entry permit | NCAA | USD 70.80 per person | No seasonal split |
| Ngorongoro Crater service fee | NCAA | USD 295 per vehicle per descent | No seasonal split |
Note the mismatch: the conservation-fee peak runs 16 May to 14 March, but the concession-fee peak is July to September only. They are not the same season. Children aged 5–15 pay USD 20 per day for conservation and USD 10 per night on concession; under-fives are free.
The VAT position matters, because it moves a Serengeti day by USD 12.60 per person. TANAPA's tariff book states that all listed charges are VAT (18%) exclusive, while its website tariff page says fees include VAT — a genuine contradiction in the authority's own material. We treat the tariff book as authoritative, quote the VAT-inclusive figure, and confirm the position with TANAPA before it goes into a costing. NCAA publishes no VAT statement for its own fees, so read USD 70.80 and USD 295 as the figures NCAA prints and nothing more.
Two more things before you build an itinerary. TANAPA's most recent published tariff book covers financial year 2023/2024, and no later book had been published as at 31 August 2026 — these are the latest official figures, but confirm them at the time of quoting. And an Ngorongoro permit is valid for one entry within 24 hours only, so a route that drops into the Conservation Area twice pays the entry permit twice. NCAA warns that its tariffs may change without prior notice, so we confirm the current figure at quote stage rather than publishing one and hoping.
TMA places Unguja and Pemba in the bimodal group, on the same calendar as the northern mainland. That is convenient: a June-to-September northern circuit safari drops straight onto Zanzibar in its driest stretch, and a February calving trip pairs with the dry transition. March to May is the one combination to think twice about — you would be taking the long rains at both ends.
The seasons line up well. In Bwindi Impenetrable Forest, the long-term rainfall record kept at Ruhija by the Institute of Tropical Forest Conservation shows June, July and August as reliably the driest months in every year of the 13-year record — the single most stable feature of that dataset. It overlaps neatly with Tanzania's June-to-September dry window.
The permit side needs planning, not luck:
One trap when you combine countries: the East Africa Tourist Visa costs USD 100 and covers only Kenya, Uganda and Rwanda. Tanzania is not part of it despite being an EAC member, so it gives you no entry rights to Zanzibar, the Serengeti, Ngorongoro or Kilimanjaro. Apply separately — USD 50 single entry for up to 90 days through the Immigration Services Department eVisa portal, or the USD 100 multiple-entry visa for US passport holders, who cannot get one on arrival.
On health, a yellow fever certificate is required if you are arriving from or transiting a risk country. The scope is set by the Tanzanian Ministry of Health rather than by Immigration, so check current Ministry guidance and a travel clinic before you fly. See our comparison of Uganda and Rwanda for gorilla trekking if you are deciding which side to add.
Check accommodation availability before you book flights, particularly for February on the short-grass plains and the northern Serengeti from August to October. No authority publishes camp occupancy, so treat any claim about how far ahead a camp fills, from us or from anyone else, as expectation rather than fact.
Tell us the month you can travel and what you most want to see. Start with planning your safari, or get in touch and we will confirm current park fees and permit availability before quoting anything. If you are weighing a Kenya–Tanzania combination, our Kenya and Tanzania migration route is built around these windows.
Safari planning team
The planning team answers permit, timing and logistics questions every day, and writes up the answers that come back most often. Everything published here is checked against current park authority rates and the routes our own vehicles drive.
